Voltage regulator



April 12,- 1938. I T. M. HUNTER 2,114,143

VOLTAGE REGULATOR Original Filed Dec. 19 1955 5 Sheets-Sheet l INVENTOR fla r was 1% er ATTORNEY April 12,1938. T, M, HUNTER 2,114,143

VOLTAGE REGULATOR Original. Filed Dec. 19, 1935 5 Sheets-Sheet 2 INVENTOR ATTORNEY 1938. v T. M. HUNTER v 2,114,143 7 VOLTAGE REGULATOR Original Filed Dec. 19, 1935 5 Sheets-Sheet 3 2'1 .5 19 a Z y 18 n 56 J 7 3 1 j 1L II 40 60 W 5 355 4952- 43 i i I 53 4745" ,i E l 44 l glll1ll 1! a; w I I I I I i 1 5 11 1 i l E i i P 1 s i l E I l B l i HI] I I 4 z I I anw' ATTORNEY April 12, 1938. T. M. .KHUNTER ,1

VOLTAGE REGULATOR Original Filed Dec. 19, 1935 5 Sheets-$heet 4 I Y I 6/ April 12, 1938. M, HUNTER 2,114,143

VOLTAGE REGULATOR Original Filed Dec. 19, 1935 5 sheds-shed 5 LOAD 55 TEST TRANS. P

208V T0 0 +51] BUCKBOOST SECONDARY LINE 2 8 INVENTOR. 7 zza5'MH zu?% BY J ATTQRNEY Patented Apr. 12, 1938 PATENT OFFICE 2,114.14: VOLTAGE REGULATOR Thomas M. Hunter. East Orange, N. J., assignor to American Transformer Company, Newark,

Application December 19, 1935. Serial No. 55,191

Renewed July 10, 1937 19 Claim.

struction and circuit arrangements have been" set forth.

The obiect of my present invention is to pro- I 15 vide still further improvements in the mechanism entering into the operation of a regulator of the type described in my prior patents, and at the same time provide a new circuit arrangement for carrying my invention into practice.

20 Other objects will appear from the description which follows. t In the drawings accompanying this specificaion,

Figure 1 is an elevational view of my new type 25 of regulator, with the casing removed.

Figure 2 is a view similar to Figure 1. but looking from right to left.

Figure 3 is apart-sectional and part-elevational view on the line H of Figure 1.

30 Figure 4 is a view taken on the plane 4-4 of Figure 3.

Figure 5 is a view on the line 5-5 of Figure 3. Figure 6 is a view on the line l,- of Figure 3, with the mechanism in one position of operation.

' 35 Figure '7 is a view similar to Figure 6, but with the parts in a different. position of operation.

Figure 8 is a view similar to Figures 6 and '7, but with the parts in a still-different position in the cycle'of operation.

40 Figure 9 is a simplified wiring diagram of the regulator circuits, minus the automatic control features.

In the various views, wherein like numbers re- V fer to corresponding parts, i represents,'broadly,

45 a framework for supporting all parts of the regulator, the outside casing not being shown in Figures 1 and 2, but the upper portion of it, 2, being shown in Figure 3. The casing 2 is provided with a closure plate I carrying a downwardly ex- 50 tending compartment 4, to the bottom wall of which is fastened a stub shaft carrying a disc 6 having a single tooth 1 (see Figure 5) which is adapted to engage notches I in a pair of Geneva gears 9 and "I. These Geneva gears are rotat- 55 ably carried with shafts ii and II that have bearings in the bottom of the compartment 4- and extend upwardly within the compartment. The shaft ll carries a switch arm l3, while the shaft I2 carries a switch arm [4. The switch arms l3 and i4 are adapted to make contact, al- 5 ternately, with contact studs 11. to p inclusive (see Figures 4 and 9), these contacts being carried by studs l5 supported on a block ii of suitable insulating material.

The compartment 4 has a cover i1 fastened 10 thereto in any satisfactory manner as by lag screws l8; one of the frame bolts I9 is shown as also passing through this auxiliary cover. Mounted on the cover I1, is a limit switch and mechanical stop 20, a gear box 2|, a motor 22, a condenser 23 used in connection with the motor,

a worm drive gear reduction 24, bearings 25 and 26, and an'operatlng shaft 21 which is supported by the bearings 25 and 26. Mounted on the shaft 21 is a sleeve carrying clutch 28 which may be operated by a member 29 to which is attached a lever. The shaft 21 carries a handwheel 3| whereby the shaft 21 and parts connected thereto may be operated by hand when the clutch, through the control rod 30, is operated to properly position the clutch for manual operation. It is to be understood that the control rod 30 extends outwardly so as to be readily operated, the same as the handwheel 3 l.

The gear box 2| contains a bevel gear 32, car- 30 ried on the shaft 21, which is adapted to mesh with a cooperating gear 33 carried on a shaft 34 supported by bearings 35. On the end of the shaft 34 is an internal gear 36 adapted to engage a pinion 31 carried on a drive shaft 30 which extends downwardly through the compartment 4 and has a bearing in the bottom wall thereof. Adjacent the outer surface of the bottom wall of the compartment 4-, the shaft 38 carries a pinion 39 which meshes with a gear 40 which 40 is also carried by the stub shaft 5 adjacent the single-tooth gear 6. r

The framework i supports a collector 4| of the commutator type, the bars of which are en gaged by brushes 42 carried on a support stud 45 member 49 may be rotated about the stud 41, being held thereon by a washer and nut 50. The sleeve 49 supports an insulator 48' on which are mounted a disc 44 and a disc 48, and a metallic member 45 fastened to the disc 44 in any satisfactory manner. Between the insulating discs 44 and 48, a pigtail 5| is positioned, one end of it being connected to the metallic member 45, which in turn is electrically connected to the stud 43 carrying the brush 42, the other end of the pigtail or flexible cable 5| being connected to another circuit element to be later referred to.

The member 49, which I refer to in the claims as a track member", more particularly shown in Figures 6, 7 and8, has an outer track portion 52 and an inner track portion 53 looped together at adjacent points 54 and 55 to form an endless reversing track. As shown in the figures, the track is in the shape of a groove formed in the member 49. Arcuately spaced within the confines of the portions 52 and 53 of the track, are projections 58 which may be made integral with the member 49, or may bev separate pins fastened thereto, but

, they are adapted to function like the teeth of a "gear to mesh with teeth on a drive gear 51. The

gear 51 is carried on the end of a stub shaft 58 which in turn is supported at the free ends of a pair of spaced bars 59 and 80'. The opposite ends of the bars 59 and 80 are oscilla'tably supported on the drive shaft 38.

Positioned between the bars 59 and 60, and fastened to the drive shaft 38, is a gear in the'shape of a sprocket wheel 8|, which is connected by a chain 82 to a second sprocket wheel 83 fastened to the stub shaft 58. Extending beyond the face of the gear 51, from the shaft 58, preferably in tegral therewith, is a projection or pin 84 which is adapted to enter the track grooves 52 and 59, so that as the stub shaft 58 is turned by the sprocket wheel 5|, chain 82 and sprocket 83, the drive gear 51 will engage the projections and thereby turn the member 49 in the direction of the arrow shown in Figure 6 It will be noted in this figure that the drive gear 51 is operating on the inner side of the projections 58. When the last projection 56 is reached, as shown in Figure 7, the pin or projection 84, moving in the track, will pass around the loop end 55 into the position shown in Figure 8, or on the opposite sides of the projections 58; Since the drive wheel 5! is turning in the same direction, it will be obvious that the direction of rotation of the member 49 will be reversed, as the frame or bar members 59 and 80'will oscillate about the drive shaft 38 to allow the drive gear 51 to take up this reversing position.

It is to be understood that the number of projections 58 on the track member 49, and the teeth.

in the drive gear, and other associated sprockets and gears, is such as to act in synchronism to move the single-tooth gear 8 and the Geneva gears 9 and I0 at certain definite intervals; that is to say, when the commutator brush 42 has reached the limit of its movement in one direction around the collector 4|, the Geneva gears 9 and I0 are operated tc'move the switch levers, either l3 or i4, alternately just before the drive gear 51 moves to its reversing position as described.

The frame I carries a main transformer 85, a buck-and-boost transformer 88, a collector transformer 61, and a reactor 88, all of which are connected as shown diagrammatically in Figure 9,

, wherein it is seen that the transformer 85 has preferably the central portion, designated as the primary, to which a source of power, having any suitable voltage, such, for example, as that marked, namely 208 volts, maybe applied. The transformer 85 has a plurality of coarse tape a to 11 inclusive connected alternately to the rotary switches l3 and I4, as indicated and heretofore referred to. The switch levers l3 and I4 serve to interconnect the coarse taps with the collector transformer 81 which has a plurality of fine taps 69; that is to say, at one or more turns, or every turn, or, if desired, at a fraction of a turn. These fine taps 89 are connected to the bars of the collector 4|, alternate taps passing through the reactor 88 as described in my Patent 1,993,007, heretofore referred to, for the purpose of eliminating sparking at the brush 42 as the same moves from one commutator bar to another.

The collector brush 42 is connected to one end of the primary winding P of the buck-and-boost transformer 85, while the other end of the primary is connected at the central point of the transformer 85. The secondary S of the transformer 88 has one end connected to the source of power, the voltage of which is to'be regulated, while the other end is connected to the primary of a load circuit illustrated in the form of a testing transformer II, the load being applied to the secondary thereof.

From what has been said, it will be seen that the operation of the regulator will be understood, as it is similar to that shown and described in my second-mentioned patent referred to in the early part of. the specification, except for this general difference: That when the switches l3 and I4 pass to one side of the central tap 10, the action on the primary P of the transformer 85 is reversed from the action when the switches are connected to taps on the opposite side of the central tap 10. When the switches I3 and 4 are on the taps h and i, and the brush is at the center of its travel around the commutator, zero voltage is applied to the winding P of the transformer 88, so that the range of regulation is from zero to double the voltage of the source of power. In the case illustrated, this regulation is from zero to 416 volts in very smooth, gradual steps.

As heretofore referred to, the regulator may be operated manually by the handwheel 8|, or automatically by the motor 22. The automatic devices are generally referred to and claimed in my Patent 1,993,007, so they are not shown in the present diagrammatic arrangement, nor described in detail herein.

What I claimis:

1. A voltage regulator including the followinginstrumentalities; at least a pair of separate transformer windings, one having coarse taps and the other fine taps, the coarse taps from one winding being interconnected to the other winding through a pair of independently operable direot-contact-making switches with means for operating the switches alternately so the circuit between the windings, including the load circuit, is never opened, a collector of the commutator' type having bars connected to the fine taps of said other winding, a brush adapted to be continuously connected to a circuit whose voltage is to beregulated, said brush being -mounted for clock and anti-clockwise rotation around said collector, and means for moving said brush at synchronous intervals between movements of said switches; further characterized in that said motions of the brush around the collector are controlled by a device including a rotatable member connected to said brush mounting to rotate the same, said rotatable memher having radially spaced arcuately formed tracks meeting to form an endless reverse loop, with a plurality of gear-engageable parts arouately spaced between the parts of the track, a gear-wheel adapted to have its teeth engage said engageable parts to rotate said member, means for rotating said gear wheel and means associated with said gear wheel cooperating with said track to cause said gear wheel to move around the last of said engageable parts at the reversible part of the loop, thereby reversing the direction of. rotation of said member.

2. A voltage regulator as set forth in claim 1, further characterized in that said track comprises a re-entrant groove in one face of said rotatable member, and said engageable parts are in the form of projecting pin-like parts adapted to mesh with the teeth on said gear, and said associated means comprises a stud-like formation, extending beyond the face of said gear into said groove.

3. A voltage regulator as set forth in claim 1, further characterized in that the rotating means for said gear wheel comprises a pair of interconnected chain sprocket wheels, one of which is fixed on a drive shaft, while the other is carried on a stub shaft supported between two bars pivotally mounted on said drive shaft, said stub shaft also carrying said gear wheel and terminating in a formation for cooperation with said track.

4. A voltage regulator as set forth in claim 1, further characterized in that said track comprises a re-entrant groove in said rotatable member and said engageable parts are projecting members adapted to mesh with said gear; further characterized in that the rotating means for said gear wheelcomprises a pair of interconnected operating members, one of which is fixed on a drive shaft; while the other is carried on a stub shaft supported between spaced bars pivotally mounted on said drive shaft, said stub shaft also carrying said gear wheel, and means extending beyond the face of said gear wheel into said groove for the purpose described.

5. A voltage regulatoras set forth in claim 1, further characterized in that said brush mounting includes a pair of spaced discs preferably of strong insulating material, said discs being arranged to rotate with said member carrying said track, a stud carried by said disc nearest the collector, the brush being carried by said stud, and a fiexible cable carried between said disc and having one end connected to said stud to complete an electrical connection to said brush as said discs and brush are rotated,

6. A voltage regulator including a casing carrying therewithin at least a pair of separate transformer windings, one having coarse taps and the other fine taps, a closure plate for the casing, a pair of independently operable rotatable switches carried on the closure plate within the casing and serving to connect said coarse taps to the other winding, a collector of the commutator type mounted within the casing below said switches andhaving the bars thereof connected to the fine taps of said other winding, cooperating means for the regulator carried on the exterior of the closure plate and including a drive shaft extending from the plate toward the collector, a pinion on said shaft, a gear rotatably mountedon a part of said plate and adapted to be operated by said pinion, a single-tooth disc operated by said gear and a pair of Geneva gears mounted for rotation at opposite ends of a diameter'of said gear, a stub shaft positioned on the axial line of said collector and carrying thereon a plurality of rotatable members, a brush, adapted to be continuously connected to a circuit, the voltage of which is to be regulated, carried by one of said members in operative engagement with the collector bars, an endless direction-reversing track carried by another of said members, driving means on said track member arcuately spaced within the confines of, the track, means including a drive gear coacting between said drive shaft and the driving means on said track member for rotating the same, and means associated with said drive gear. and shaft for cooperating with the track for reversing the direction of action of the drive gear on said track member driving means, the various gears and interconnected parts being constructed and arranged so the said brush is moved at synchronous intervals between alternate movements of said Geneva gears.

7. A voltage regulator as set forth in claim 6, further characterized in that the closure plate for the casing carries a compartment within which said pair of switches are mounted.

8. A voltage regulator as set forth in claim 6, further characterized in that the closure plate I for the casing carries a compartment within which said pair of switches are mounted, said compartment opening through the closure plate and having a cover for said opening, while said regulator-operating means is mounted on said cover with the said drive shaft extending through said switch compartment, and having a bearing in a wall thereof, while the pinion, driven gear and Geneva gears are also mounted for rotation on a wall of the compartment.

9. A voltage regulator as set forth in claim 6, further characterized in that the closure plate for the casing carries a compartment within which said pair of switches are mounted, said compartment opening through the closure plate and having a cover for said opening, while said regulator-operating means is mounted on said cover with the said drive shaft extending through said switch compartment, and having a bearing in a wall thereof, while the pinion driven gear and Geneva gears are also mounted for rotation on a wall of the compartment, and further characterized in that the operative connection between the said drive shaft and the track member includes; a pair. of spaced barsoscillatably mounted on the inner end of said shaft adjacent said pinion, a pair of sprocket wheels having interconnected operating means and positioned between said bars, one wheel being fast, on said drive shaft, while the other is fixedly carried on a stub shaft rotatably supported at the free end of said bars, said drive gear for operating said track member being on the end of said stub'shaft.

10. A voltage regulator as set forth in claim 6, further characterized in that the operating means on the closure plate may be either manual or automatic, with means for shifting from one to the other.

Iii. A voltage regulator including the following instrumentalities; at least a pair of separate transformer windings, one having coarse taps and the other fine taps, the coarse taps from one winding being interconnected to the other winding through a pair of independently operable direct-contact-making switches with means for operating the switches alternately so the circuit between the windings, including the load circuit, is never opened, a collector-of the commutator type having bars connected to the fine taps of said other winding, a brush adapted to be continuously connected to a circuit whose voltage is to be regulated, said brush being mounted for ,clock and anti-clockwise rotation around said collector, and means for moving said brush at synchronous intervals between movement of said switches; further characterized in that special means are provided for reversing the direction of rotation of said brush about the collector after it has reached its full travel in one direction, said means including a member mounted for simultaneous rotationwith the brush, said mem, her having arcuately arranged radially spaced portions joined at spaced points into an endless track, with arcuately spaced projecting parts within the confines of the track, a driving gear wheel adapted to engage said projecting parts to turn said member, and means engaging said track to cause said gear wheel to move from one side of said projecting parts to the other side thereof, thereby automaticallyreversing the direction of rotation of the track member when the brush has reached its full travel in one direction.

12. A voltageregulator including the followin instrumentalities; at least a pair of separate transformer windings, one having coarse taps and the other fine taps, the coarse taps from one winding being interconnected to the other windchronous intervals between movement of said switches; further characterized in that special means are provided for reversing the direction of rotation of said brush about the collector after it has reached its full travel in one direction, said means including a member mounted'for simultaneous rotation with the brush, said member having arcuately arranged radially spaced portions joined at spaced points into an endless track, with arcuately spaced projecting partswithin the confines of the track, a driving gear wheel adapted to engage said projecting parts to turn said member, and means engaging said track to cause said gear wheel to move from one side of said projecting parts to the other side thereof, thereby automatically reversing the di-- rection of rotation of the track member when the brush has reached its full travel in one direction, and further characterized in that the track is in the form of a groove within which said engaging means moves, said driving gear wheel being mounted on a driving mechanism that can oscillate about a driving center, whereby said driving gear can follow the directions imposed by the track.

13. A brush-reversing mechanism for'a voltage regulator of the kind herein described including,

' a drive shaft, 2. member for operating the brush,

said member having arcuately arranged radially spaced portions joined in series to form an endless loop reversing track, arcuately spaced projections within the confines of the track, a gear wheel for engaging said projections, .said gear wheel being carried on a mounting which is oscillatably positioned on said drive shaft, means for turning said gear wheel from said drive shaft, and means cooperating between said track and mounting to cause said gear wheel to move so as to engage said spaced projections on opposite sides thereof when the loop ends of the track are reached by said means.

14. A brush-reversing mechanism for a voltage regulator as set forth in claim 13, further characterized in that said gear wheel mounting comprises, two spaced bars oscillatably supported on the drive shaft, a pair of sprocket wheels with a chain interconnecting them, one wheel being fast on the shaft between said bars, the other fast on a stub shaft carried at the free ends of said bars, the gear wheel being mounted on the end of the stub shaft which has a projection comprising said cooperating means, while the said track is in the form of a groove within which said cooperating projection moves.

15. In a voltage regulator of the type herein described wherein a collector of the commutator type has its bars connected to the fine taps of a transformer winding and a pair of rotary switches have their alternate contacts connected to coarse taps on another transformer winding, the rotating arms of said switches being connected to the first-mentioned winding and the collector is provided with a brush mounted for rotation around the collector, said brush being connected continuously in a circuit whose voltage is to be regulated; further characterized in'that said switch arms and brush are operated by devices connected to a drive shaft which may be controlled manually and automatically, the brush operating devices including a disc-like member having a reversing endless groove in one face thereof with gear-engageable parts arcuately spaced within the confines of the groove, and a drive gear oscillatably mounted on and indirectly driven from said drive shaft, and means moving in said groove for causing the drive gear to move so as to engage said gear-engageabie parts on opposite sides thereof, thereby reversing the direction of rotation of said disc-likemember, the reversal being synchronized with the movement of said switch arms as and for the purpose described.

16. A voltage regulator including a transformer having, in effect, a continuous winding. the central section of which comprises the primary and adapted to have a source of power connected thereto, the winding having coarse taps therefrom, a second transformer having a winding with fine taps, a pair of independently operable direct contact makingswitches serving to interconnect the coarse taps to the second-mentioned transformer winding, means for operating the switches alternately so the circuit between said windings, including the load circuit, is never opened, a collector of the commutator type having bars connected to said fine taps, a buck-and boost transformer having win thereon, the

end of one winding being connected to the center coarse tap switches move to opposite sides of said central tap, the said huck-and-boost transformer will be caused to'huck or boost the voltage impressedonitsprimarybythesourceofpower.

. 18. A voltage regulator as set forth in claim 16,

further characterlaed in that when the saidcoarse tap switches move to oppodte sides-of said central tap, \the said b'uck-and-hoost transformer will becausedto buckvorboostthe voltage impressed on its primary by the source of power, further characterized in that when the said switches are connected-to taps immediately adhas a range from zero to substantially twice the 10 primary voltage applied to said transformer.

- THOMAS M. HUNTER. 

